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Power Integrations beefs up CapZero X-cap discharger

Power Integrations has announced a second generation of its novel CapZero discharger chip for mains X-capacitors.

X-capacitors can hold chargeThe amount of electricity present upon the capacitor’s plates. Also, the act of forcing of electrons onto the capacitor’s plates. See CoulombA coulomb is the unit of electric charge. It is named after Charles-Augustin de Coulomb.1 coulomb is the amount of electric charge transported by a current of 1 ampere in 1 second. It can also be defined in terms of capacitance and voltage, where one coulomb is defined as one farad of capacitance times one volt of electric potential difference.. after mains-powered equipment is turned off. Without a discharge device, this can result in residual high-voltage being present, for example, on a disconnected mains plug.

The simplest discharger is a resistor, but using one results in constant power dissipation.

CapZero is a two terminal integrated circuit that remains in a high-impedanceThe total opposition that a circuit offers to the flow of alternating current or any other varying current at a particular frequencyThe number of complete cycles or vibrations per unit of time. Rate of alternation in an AC current. Expressed in cycles per second or hertz (Hz).. It is a combination of resistance R and reactance X, measured in ohms. state (21.7uAmax at 25C = 5.2mW at 240V) when mains frequencyThe number of complete cycles or vibrations per unit of time. Rate of alternation in an AC current. Expressed in cycles per second or hertz (Hz). is connected, then switches to a low impedanceThe total opposition that a circuit offers to the flow of alternating current or any other varying current at a particular frequencyThe number of complete cycles or vibrations per unit of time. Rate of alternation in an AC current. Expressed in cycles per second or hertz (Hz).. It is a combination of resistance R and reactance X, measured in ohms. state when mains frequencyThe number of complete cycles or vibrations per unit of time. Rate of alternation in an AC current. Expressed in cycles per second or hertz (Hz). is removed, rapidly discharging the capacitor. Discharge current is limited by a series resistance totalling 142k to 7.5Mohms. THis resistance is split in two. “The external resistors in this case are divided into two separate surface mount resistors to distribute loss under fault conditions – for example where a short-circuit exists between CAP200DG terminals,” said he firm.

CapZero-2 can handle a wider range of capacitors than the original – now from 0.1µFUnit of capacitance. The basic unit of a measure of a capacitor. A capacitor charged to 1 volt with a charge of 1 coulombA coulomb is the unit of electric charge. It is named after Charles-Augustin de Coulomb.1 coulomb is the amount of electric charge transported by a current of 1 ampere in 1 second. It can also be defined in terms of capacitance and voltage, where one coulomb is defined as one farad of capacitance times one volt of electric potential difference. would have a capacitance of 1 farad. 1 microF = .000001 Farads. to 6µFUnit of capacitance. The basic unit of a measure of a capacitor. A capacitor charged to 1 volt with a charge of 1 coulombA coulomb is the unit of electric charge. It is named after Charles-Augustin de Coulomb.1 coulomb is the amount of electric charge transported by a current of 1 ampere in 1 second. It can also be defined in terms of capacitance and voltage, where one coulomb is defined as one farad of capacitance times one volt of electric potential difference. would have a capacitance of 1 farad. 1 microF = .000001 Farads. – and voltages up to 1kV (6kV transient). The orignal CapZero was a range of products, with the same quiescent current, rated at either 825 or 1,000V, and up to 5µFUnit of capacitance. The basic unit of a measure of a capacitor. A capacitor charged to 1 volt with a charge of 1 coulombA coulomb is the unit of electric charge. It is named after Charles-Augustin de Coulomb.1 coulomb is the amount of electric charge transported by a current of 1 ampere in 1 second. It can also be defined in terms of capacitance and voltage, where one coulomb is defined as one farad of capacitance times one volt of electric potential difference. would have a capacitance of 1 farad. 1 microF = .000001 Farads..

Other specifications between first and second generations are almost identical.

Second generation products are safetyClass X capacitors are used in “across-the-line” applications where their failure would not lead to electric shock. Class X safety caps are used between the “live” wires carrying the incoming AC current. In this position, a capacitor failure should not cause any electrical shock hazards, rather, a capacitor failure “between-the-lines” would usually cause a fuse or circuit breaker to open.-certified to CB and Nemko requirements, developers do not need to perform a separate capacitive discharge safetyClass X capacitors are used in “across-the-line” applications where their failure would not lead to electric shock. Class X safety caps are used between the “live” wires carrying the incoming AC current. In this position, a capacitor failure should not cause any electrical shock hazards, rather, a capacitor failure “between-the-lines” would usually cause a fuse or circuit breaker to open.testtest is test of the power circuit.

“CAPZero-2 allows power supplies to comply with IEC 62368-1, the new over-arching safetyClass X capacitors are used in “across-the-line” applications where their failure would not lead to electric shock. Class X safety caps are used between the “live” wires carrying the incoming AC current. In this position, a capacitor failure should not cause any electrical shock hazards, rather, a capacitor failure “between-the-lines” would usually cause a fuse or circuit breaker to open. standard covering a broad segment of energy-using equipment. The standard replaces IEC 60950 and IEC 60065, and will shortly become mandatory,” said the firm.